1. Field of the Invention
The present invention relates to an electrically operated vehicle drive controller and an electrically operated vehicle drive control method.
2. Background Art
A planetary gear unit having a sun gear, a ring gear and a carrier is conventionally arranged in a vehicle drive unit mounted to a hybrid vehicle as an electrically operated vehicle and transmitting one portion of engine torque (as torque of an engine) to an electric generator (electric generator motor) and transmitting the remaining engine torque to a drive wheel. The sun gear and the electric generator are connected to each other. The ring gear, a drive motor and the drive wheel are connected to each other. The carrier and the engine are connected to each other. Driving force is generated by transmitting rotation outputted from the ring gear and the drive motor to the drive wheel.
In the vehicle drive unit, the electrically operated vehicle drive controller is arranged to adjust the engine torque transmitted to the drive wheel. This electrically operated vehicle drive controller calculates inertia correcting torque by subtracting inertia torque (as torque of an inertia amount of the electric generator) from electric generator target torque which is a target value of electric generator torque (as torque of the electric generator). The electrically operated vehicle drive controller presumes drive shaft torque constituting torque outputted from a drive shaft as output torque on the basis of this inertia correcting torque. With respect to vehicle request torque required to run the hybrid vehicle, excessive and deficient amounts of the output torque are compensated for by driving the drive motor (see e.g., JP-A-8-295140).
However, in the conventional electrically operated vehicle drive controller, for example, angular acceleration of the electric generator is required to calculate the inertia torque. However, this angular acceleration is influenced by a detecting error, etc. of a position sensor for detecting a rotor position and is changed. Accordingly, the angular acceleration includes a disturbance component of a noise shape so that the inertia torque also includes the disturbance component of the noise shape. Hence, vibration is generated in the hybrid vehicle when the drive motor is driven by drive motor target torque which is a target value of drive motor torque (as torque of the drive motor) calculated on the basis of the inertia torque.
Therefore, it is considered that, in order to restrain the disturbance component of the noise shape from being included in the angular acceleration, the angular acceleration is presumed by using a filter in calculating the angular acceleration or a means of state presumption, etc. However, when the filter is used in calculating the angular acceleration, the disturbance component of the noise shape can be removed, but delay is caused in the calculation of the angular acceleration and vibration can not be restrained. Further, there is a case in which the vibration is increased. In contrast to this, when the angular acceleration is presumed by the means of the state presumption, etc., an error is caused between the presumed angular acceleration and the actual angular acceleration by a mechanical difference between a model used in the state presumption and the actual vehicle drive unit so that the vibration is generated.